Conveyer system



Aug. 31, 1943. R's. M'ccAflN CONVEYER SYSTEM Filed July 10, 1940 5Sheets-Sheet l Aug. 31, 1943. P. s. MCCANN 2,328,386

GONVEYER SYSTEM Filed Jul lo, 1940 ,3 Sheets-Sheet 2 Aug. 31, 1943.

P s. M CANN CONVEYER SYSTEM Filed July 10, 1940 l 3 SheetsSheet 3 FIG. 7

vator's.

Patented Aug. 31, 1943 Fries ooNVEYER SYSTEM Application July 10, 1940,Serial No. 344,684

, 17 Claims.

inventionrelates to conveyer systems, and more particularly to conveyersystems of the type in which articles are conveyedfrom a pluralityofseparate workstations andare deliveredtto a commonmain conveyer.

Objects, of the invention areto'provide, in a conveyor system of thetypereferred to, simple and reliable mechanism for controlling the deliveryofthe articlesto the main conveyenwhereby collision between thearticlesare'avoided.

In accordanceiwith one embodiment ofthe inventionvthereis providedaconveyer system in which a continuously moving conveyer belt isarranged to receive articles orpackages from a series of separateconveyers or elevators spaced along theconveyerbelt- Mechanism isprovided for controlling the transferof packages from the severalelevators to the conveyer belt, whereby jamming or piling up oilpackages on thecon- ,veyer belt is prevented.

1 A preferred embodiment of the invention is illustrated v in theaccompanying drawings, in which j I e Fig. 1 is a planviewof a, conveyersystem em bodying the invention; y

s Fig. 2 is an enlarged vertical sectional view takenonline22 ofFig.1; U

Fig. 3 is anyenlarged vertical sectional view taken on line 3-4 ofFig.1; I

Fig. 4 is an enlarged plan view of onelof the elevators; I," Q I Fig. 5is an enlarged fragmentary sectional view siimlar to the upper portionof Fig. 2, but showing the elevator carriers advanced from the positionsinwhich they are shown in Fig.2; h

Fig. 6 is a fragmentary plan section taken on line 64 of Fig. 2, and

Fig. 7 is a wiring diagram of the electrical control mechanism em oyedat each of the ele-,

, As illustrated somewhat schematically in Fig. 1, the conveyersystemcomprises, a series of separate conveyors orelevators HI, ID eachadaptedto receive packages II, II from anassociated work table or packingbench," and "carry the same to, a commonoverhead conveyer belt I I. Thisconveyer belt travels in a sheet metal channel l5 and is adapted to becontinuously driven by suitable means (none shown) so as to convey thepackages, to a shipping platform or to any other desired destination. rh l The several elevators are all identical in construction andoperation and, therefore, a descriptionof meet them willsufllceQEachelevator comprises a structural steel shaft l1 within whicha pair of endless chains I8, l8 are arranged to travelaround uppersprocket wheels l9,;|9' and lower sprocket wheels 20, 201 The two uppersprocket wheels are attached to a rotary shaft 22 and the two lowersprocket wheels are fixed to a driven shaft 23. a The shaft 23 maybedriven by any suitable means, preferably through a speed reducer 25driven by an electric motor 25.

The elevatorchains are eachequipped with a plurality of equidistantlyspaced lugs-28 upon whichpackage carriers 30 are pivotally suspended.These carriers comprise horizontal portions 3| which project inwardly sothat the carriers on one chain cooperate with opposed carriers on theother chain to provide shelf-like supports for receiving and supportingthe packages H, as ilelevating chains, and the packingbenches l2 aredisposed on the upwardly moving sides ofthe elevator chains near thelower ends of theelevators. Each elevator has a separate packing benchassociated therewith, but since the several benches and associatedmechanisms are of identical construction, a description offone of themwill suffice.

The top of each bench has a slot 36 which extends longitudinallyof thebench top and in line with theelevator carriers. Thisslot together witha pair of plates 31, 3] attached to the underside of the "bench topformsa trough or guicleway along which the packages are adapted to 'beadvanced towardthe elevator by means of a series of pusher bars 40, 40attached to a loading chain 4| disposed belowthebenchtop (Fig. 2). Theplates; 31 are spaced apart to permit the pusher bar to passtherebetween and the pusher bars are equipped with thrust rollers 42, 42(adapted to ride along the upper surfaces of' the plates.

The pusher bars are adapted to advance the packages along the horizontalplates 31 and onto the inner end portions thereof which extend into theelevator shaft between the upwardlymoving sides of the two elevatorchains 18. The inner end portions of the plates are notched, asindicated at 44 (Fig. 6), to permit the passage of the upwardly movingelevator carriers 30, and it will be noted that the ends of the packagesll overlap the notched portions of the plates and are thus automaticallylifted from the plates by the upwardly moving carriers. The loadingchain 4! is driven from the same shaft 23 which drives the elevatorchains, whereby the movement of the pusher bars 40 is synchronized withthe movement of the upwardly moving elevator carriers. Thus, the loadingchain pusher bars advance the packages, one at a time, onto the notchedinner end portions of the plates 31 in timed relation with the upwardlymoving elevator carriers 30, which automaticallylift the packages fromthe plates and carry them upwardly for delivery to the overhead conveyerbelt l4.

' transfer of packages from the elevator carriers to the, conveyor beltsothat. they will not interfere with other packages on the conveyer beltwhich may'have been previously delivered thereto by other elevators.This mechanism comprises a tiltable transfer platform 45, which ispivotally mounted upon .a horizontal pin 45 near the upper end of theelevator and com rises a substantially flat and normally horizontalplated! disposed between the downwardly moving sides of the elevatorchains above the level of the conveyor belt. The transfer. platformfurther comprises a dependingarm 48 adapted to engage a fixed stopbracket 49. A rearwardly extending arm 59 of the platform carriesanadjustable counter-weight for holding arm 48- against stop 49 so thatthe platform plate 41 is normally maintained in a horizontal position.HoWeven'theweight of a package l I, when placed upon the platfor-mplate,

is suiiicient to overcome the countereweight and tilt the-platform platefrom its horizontal position to theincl-ined position indicated indotted lines in Fig. 5, whereby the package is caused to slide down theplatform :plate and ontov the continuously moving conveyer belt Hi.

A spring-pressed latch 53 normally cooperates with the depending arm 48of the platform to prevent tilting of theplatform under the weighto'fapackage placed thereon. Thus, the package is retained on the platformplate 41 until the latch is retracted. An electromagnet or solenoid 55is provided for retracting the latchand the energizing circuit for thissolenoid is controlled by two mercury switches 51 and 53. Switch 51 issuitablymounted above the conveyor belt l4.- It is normally closed andadapted to be opened by .oncoming packages on the conveyor belt as theyapproach the point of delivery of packages, from the transfer platformto th cenveye'r belt. The oncoming packages engageand elevate ahorizontal shoe 6D, pivotally connected'to. an operating A continuously[driven horizontal roller 43 is provided for closarm 59 of the switch51, thereby opening the switch. This de ienergizes thelatchretractingsolenoid and, therefore, the latch prevents tilting of the platformtodischarge a package onto .the conveyor belt. After the package on thecon-.

veyer belt has passed beyond the point of delivery of packages from thetransfer platform, switch .5] automaticallycloses and thus condition the.energizingcircuit of the latch retracting solenoid sothat upon theclosing of switch 58 this cirsuit is established. The solenoid will thenretract the latch and thereby permit tilting of the platform under. theweight of a package thereon, whereby the package wil be discharged ontothe conveyor belt.

'chronism with the elevator chains.

ated by the lugs 28 on one of the elevator chains.

charge of packages from the transfer platform.

The electrical operating circuit for the elevator 'motor 26 iscontrolled by two switches 54 and which are connected in parallel, asshown in Fig. '7. Both of these switches are normally closed. Switch '65is attached to the underside of the platform plate 47. Its operatingbutton projects through the platform plate and is adapt-- ed to bedepressed by a package when placed upon the platform. This switch is"thereby opened, but the elevator motor continues to run until switch 55is also opened. This latter switch is mounted adjacent the uppersprocket shaft fz and is adapted to be opened by a cam 6? fixed to thisshaft. The function of switch '55 is to permit the elevator chains totravel sufficiently to close switch 58 after each carrier passes by thetransferplatform. The closing of switch .58 before stopping the elevatorchains is essential in order to insurethat the energizing circuit oflatch retracting solenoid 55 is conditioned to be closed as soon as theconveyer'belt M is free to receive a package from the transfer platform.

The electrical circuit for theelectrical control mechanisms at one ofthe elevators is illustrated diagrammatically in Fig. 7, and it Will'beUI Qermally closed switches 6A and 65. .The elevator chains are thusdriven by the motor in the direction indicated by the arrows in Fig. 2,and the loading chain 4! is simultaneously-driven in yn- Packages placedin the table groove 36 are automatically loaded onto the elevatorcarriers as, which carry the packages upwardly and place them, one at atime, upon the transfer platform 45, as explained above. Each package,when placed on the transfer platform, opens the normally closed switch54 Y in theelevator motor circuit. The elevator motor continues to run,however, on electrical current suppliedthereto through normally closedswitch.

the packages onto the belt.v The solenoid, upon being energized,retracts the latch 53, whereupon the transfer platform is tilted by theweight of the package and the package is thereby discharged onto theconveyer belt. However, since the energization of the latch retractingsolenoid requires the closing of both switches 5! and 58, no tilting ofthe transfer platform to discharge the package; can "occur unless thereare no packages on the fconveyer belt "opposite the transfer plat form,sincesuch packages would hold open the switchi'l, Thus jamming or'pillngup or packages on the'conveyer belt-[is positively prevented.

Normally closed switch j 65 in the; elevator motor circuit isr'nomentarily opened bycanr 61 1,

simultaneously with each "closing" of solenoid eon;

trolling switch 58. However, since the stopping of the elevator motorrequires the opening of both switches 64 and 65, the movement of theelevator is not interrupted by the momjentaryopening of switch is unlessswitch 1541s,; atthe same time,

held openby a package previously-placeduponthe atrestuntil the packageisdischarged. This pre ventsthe pilingup oflpackagesiupon the transferplatform, Switch 58 is arranged so th'atit mg the ar r a a kage fr m thetransfer platform, whereby the energizing circuit for-th latchretracting solenoid is conditioned to be closed immediately upontheolosing of switch ELQ'I'hnsythetransfez "platform is ca1 1sed todischarge the package as soon as the conveyer belt is ready toreceiveit. The discharge ofthe package from the transfer platform permitsswitch 64 to close Land therebyd e-start,theele vator. fSwitch Mme-opensbefore thenext set of carriers places another package upomthe transferplatform and remains open until thecarriersare again positioned so asnot to interfere with the discharge of the package from the transferplatform.

, The transfer of packages from each of the several elevators to themain "conveyer belt is controlled in the same manner as described notlimited to the particularembodiments there--. of herein illustrated anddescribed, except insofar as is defined by the appended claims.

What is claimed is:

r 1. In a conveyer system, a main conveyer, a second conveyer forconveying articles toward said main conveyer, a transfer platform forreceiving articles from the second conveyer, said platform being movableto discharge said articles onto said main conveyenand means controlledbyarticles on the main conveyer for controllingelevator]cooperating'therewith c' mpr'isin'ga series remainsclosed whilethe elevatorisatrest Dend- *ofcarriers for articles to be delivered to"said fplatfornil 1 4 f In a -conveyer system, a main conveyer, "asecondconve'yer for conveying articles to said main conveyer, a hingedplatform for transferring articles from said second conveyer to saidmain conveyer, latch means normally preventing tilting of said platform,andmeans under the con trol of articles being conveyed by the mainconveyer forreleasing said latch means to permit tilt jg offsaidplatform to dischargearticles therefrom ontosaidmain conveyer. 4 i

In a conveyer system, a main conveyena second conveyer for conveyingarticles to said main conveyer, a tiltableplatform for transferringarticles fromsaid second conveyer to said mairriconveyergsaid secondconveyer comprising' a series ef carriers adapted to. place the articles'uponsai'd platformjfand means under the control oflarticlesqon saidmain conveyer for controllingethe discharge of articles rrom'samanison'vjeyersystem, a main conveyer, an

mainconveyer, aj t ransfer platform for receivingoarticles from saidcarriers for delivery to said 'elevatorfor conveying articles tosaidmainbonveyer,saidelevator comprising a eries of carriers each;adapted to support an article, a transfer platform for receivingarticlesfrom said carriers for delivery to said main conveyer, meansunder the movement of saidtransfer platform.

2. In a conveyer system, a main conveyer, an elevator for conveyingarticlesto said main conveyer, transfer means for transferring articlesfrom said elevator to said main conveyer, latch means normallyrestraining said transfer means, and means under the Joint control ofsaid elevator and articles on the main conveyer for releasing said latchmeans;

, 3. In a conveyer system, a main conveyer, a

second conveyer for conveying articles to ,said

main conveyer, a hingedtransfer-platform for' receiving articles fromsaid second conveyer, said platform being tiltable to'dischargesaidarticles onto said main conveyer, and means controlled by articles onthe main conveyer for controlling the tilting of said transfer platform.

plurality of elevators for conveying articles to said mainconveyer, atransfer platform associated with each elevator for transferringarticles therefrom to said main conveyer, and means 'under the controlof articles on the main conveyer for controlling the operation of theseveral transfer platforms, whereby piling up of articles on the mainconveyer is prevented.

9. In a conveyer system, a plurality of separate.

article-conveying elevators, a conveyer belt for receiving articles fromsaid elevators, a hinged platform at each elevator for receivingarticles therefrom for delivery to said conveyer belt, said platformbeing tiltable under the weight of an article when placed thereon by theelevator,

whereby the article is discharged onto said conveyer mlt, and latchmeans under the control of articles on the conveyer belt forpreventingtilting of said platform.

10. In a conveyer system, a main conveyer, a

second conveyer for conveying articles to the main conveyer, transfermeans for transferring articles from the second conveyer to said mainconveyer, releasable means normally restraining said transfer means, andmeans under the joint control of the second conveyer and articles on themain conveyer for releasing said restraining means. i

11'. In a conveyer system, a, main conveyer, a second conveyer fordelivering articles to said ma-in conveyer, a hin ed transferiglatformfor receiving articlesfrom said second conveyer, said platformbeing til-table to discharge said articles onto said main conveyer, andmeans underJthe joint control of said second conveyer and articles onthe main conveyer for controlling the tilting of said transfer platform.i a

12. In a conveyer system, a main conveyer, a second conveyer forconveying articles to said main conveyer,. atransfer mechanism forreceiving articles from said second conveyer for delivery to said mainconveyer, means under the control of articles received by the transfermechanism for controlling the secondccmveyer,v and means under thecontrol of said second conveyer for controlling the delivery of articlesfrom said transfer mechanism to said main conveyer.

(13. Ina conveyer system, a main conveyer, a second conveyerforconveying articles to said main conveyer, a transfer mechanism forreceiving articles from said second conveyer for delivery to said mainconveyer, means under the control of articles received by the transfermechanism for controlling the second conveyer, and means under thecontrol of articles on the main ,conveyer for controlling the. deliveryof articles from said transfer mechanism to saidmainiconveyer. r I

14, In aconveyer system, a main conveyer, a second conveyer forconveyingarticles to said main conveyer, a transfer mechanism for receivingarticles from said second conveyer for delivery to said-main conveyer,means under the control of articles received by the transfer mechanismfor controlling the second conveyer, and

means under the joint control of said second conveyer and articles onthe main conveyer for controlling the delivery of articles .from thetransfer mechanism to said main conveyer.

15. In a'conveyer system, a main conveyer, a second conveyer forvconveying articles .to the main conveyer, a transfer mechanism forreceiving articles from the second conveyer for delivery to the mainconveyer, a series of spaced elements on saidsecond conveyer, and meansunder the control of said elementsfor controlling the delivery. ofarticles from said transfer mechanism to said main conveyer. 3

16. In a conveyersystem, a

main conveyer, a

second conveyer for conveying articles to the ing articles from thesecond conveyer for delivery I to the main conveyer, a series of switchoperating elements spaced alongthe second conveyer and, movabletherewith, a switch arranged to be operated by, said elements, a secondswitch adapted to be'operated by articles on the main conveyer, andmeans under thejoint control of the two switches for controlling thedelivery of articles from the transfer, mechanism to said main conveyer.

' PAUL S. MCCANN.

